In malignant transformation fibroblasts lose a glycoprotein, fibronectin, from cell surface and production of alpha 2-macroglobulin. We plan to extend our studies on 1) characterization of fibronectin metabolism and distribution in cultured cells 2) Evaluation of clinical significance of fibronectin determinations in human body fluids 3) Distribution of fibronectin in normal and pathological human tissues 4) Mechanism of fibronectin release from transformed cell surfaces 5) Characterization of alpha2-macroglobulin metabolism in normal and malignant cells in culture. BIBLIOGRAPHIC REFERENCES: Keski-Oja, J., Vaheri, A., and Ruoslahti, E. Fibroblast surface antigen (SF): The external glycoprotein lost in proteolytic stimulation and malignant transformation. Int. J. Cancer 17, 261-269, 1976. Keski-Oja, J., Mosher, D., and Vaheri, A. Dimer character of fibronectin, the major fibroblast surface-associated glycoprotein. Biochem. Biophys. Res. Comm., 74, 699-706, 1977.